1. Field of Invention
The invention relates to the construction of an ink-jet head and a method of fabricating same.
2. Description of Related Art
An on-demand type ink-jet printer head using piezoelectric elements is disclosed in Japanese Patent Application Publication No. 8-276586. In the disclosed ink-jet head, a head unit is bonded, using an adhesive, to a head case made of a synthetic resin.
The head case is molded by injection of a synthetic resin. However, due to a fabricating error, an adhesive interposed between the head case and the head unit may be squeezed out. If the squeezed adhesive makes contact with ink to be supplied to the head unit, chemical reaction occurs. As a result, adhesive particles are dispersed into the ink and cause an ink ejection failure and ultimately clogging of the nozzle.
If the ink permeates into the adhesive, the ink may leak to the outside with the aid of air bubbles contained in the adhesive.
Another problem is that an ink-jet head is hard to fabricate with a high degree of accuracy by bonding using an adhesive. Especially, when a plurality of head units are bonded to a single head case, the mounting accuracy should be improved between the head units and the head case as well as between the head units. If such mounting accuracy is low, the direction and angle of the ink ejected from the nozzle becomes unstable, resulting in poor printing quality.